Duct Blower Therory Quiz

1. Question

Which of these measurements would be classified as exemplary duct-leakage?

2 CFM25 per 100 ft2 or floor space
6 CFM25 per 100 ft2 or floor space
10 CFM25 per 100 ft2 or floor space
20 CFM25 per 100 ft2 or floor space

2. Question

With the air handler operating, where would you find the highest positive pressure in the duct system?

In the supply plenum.
In the return plenum.
In the largest return grille.
In the closest supply register.

3. Question

Which of these choices can measure duct leakage?

Duct blower and manometer.
Pressure pan and manometer.
Analog manometer.
Hot-wire anemometer.

4. Question

Which of the following is true about duct insulation?

It is a good idea for any ducts in unconditioned spaces.
It is required for all ducts in conditioned spaces.
It is only necessary in severe climates.
It is not necessary on crawl-space supply ducts.

5. Question

Which of the following isn’t an approved a ceiling material

Gray fabric duct tape.
Duct mastic.
Aluminum FSK tape.
Products marked UL 181 – B

6. Question

What is the best location for all parts of the duct system?

Inside the thermal envelope.
In the crawl space or attic.
In the floors and walls.
Outside the building envelope

7. Question

What is the most common pressure when testing duct leakage?

25 Pascals
50 Pascal
0 Pascals
15 Pascals

8. Question

Why do supply duct leaks usually waste more energy than return duct leaks?

They leak conditioned air.
They’re bigger than return leaks.
They operate at a higher pressure.
They’re easier to seal.

9. Question

Which duct leaks are the highest risk to the health and safety of the building’s occupants?

Return leaks.
Supply leaks.
Air handler leaks.
Duct boot leaks.

10. Question

How could duct leakage still waste energy if the duct system is completely inside the building envelope?

It causes zone pressure imbalances.
It slows the movement of air through the ducts.
It causes the filter to get clogged faster.
It makes the air handler run faster.

11. Question

How are leaky return ducts in a combustion appliance zone a potential safety hazard?

They can pull flue gases into the house.
They can stop the water heater from lighting.
They can push furnace flue gases into the heat exchanger.
They can stop the carbon monoxide alarm from working.